1. Field of the Invention
The present invention relates to an arrester and, in particular, to an arrester having a compact size and good heat dissipation capability.
2. Description of Related Art
A general power line mostly is mounted at the outdoor. Under a lightning strike, the power line will produce a high voltage of up to several thousand volts. If such a high voltage goes through the power line and enters buildings, it is easy to damage electrical appliances connected to the power line.
A conventional arrester uses an isolation transformer for lightning isolation. The high voltage due to lightning is isolated on the primary side of the isolation transformer, preventing the circuit on the secondary side of the isolation transformer from being damaged by the lightning occurring on the primary side.
The above-described isolation transformer has a problem of large volume. For electronic products used in a limited space, the isolation transformer would occupy quite a large portion of the space. When the isolation transformer is connected to AC power, the isolation transformer produces heat due to the impedance of its internal circuit. For the above-mentioned electronic products that use arresters having the isolation transformer, problems such as limited space, heat dissipation and size all pose a challenge in circuit designs and circuit board layouts.